Soak the rice in hot water, whil you prepare the other ingredients
Cut the cucumber in half lengthwise. Using a spoon, scoop out the seeds from each half.
Cut the cucumber half lengthwise again, creating quarters, and slice into 2 cm pieces.
Place the cucumber pieces in a pan with approximately 4 tablespoons of water. Add the cinnamon, curry powder, turmeric, pandan leaves, curry leaves, chilli, and salt at the same time. Stir well.
Cook on low heat, stirring occasionally, until the cucumbers are fork-tender. Do not add the coconut-mustard mixture yet.
Using a hand blender or food processor, purée the soaked rice, desiccated coconut, onion, garlic, mustard, pepper, and coconut milk until smooth.
Only once the cucumbers are fork-tender, add the coconut-mustard mixture. Stir well and simmer for an additional 5 minutes.